KR20070078332A - Dynamic range controlling apparatus and method of weight vectors corresponding to combing formula in a mobile station equiped with multiple antennas in a high speed packet data system - Google Patents

Abstract

An apparatus and a method for controlling a dynamic range of a weight according to a combining formula of a terminal using multiple antennas in a high speed packet data system of CDMA are provided to control a dynamic range of a weight multiplied to a PN-descrambled signal in a mobile terminal. A channel estimator(202) receives a pilot symbol transmitted from a base station and calculates a channel estimated value of a reception path of each antenna. An autocorrelation matrix calculator(204) calculates an autocorrelation matrix value at every chip interval determined from the received pilot symbol. A weight vector calculator(206) calculates a corresponding weight vector by using the channel estimated value and/or autocorrelation matrix value according to a combining method selected according to a channel environment. A controller(208) determines whether to correct the weight vector according to the selected combining method, and when the weight vector needs to be corrected, the controller outputs a corrected weight vector by using a scale factor. A combiner(210) outputs a combining signal by multiplying the weight vector outputted from the controller to a descrambled signal.

Description

DYNAMIC RANGE CONTROLLING APPARATUS AND METHOD OF WEIGHT VECTORS CORRESPONDING TO COMBING FORMULA IN A MOBILE STATION EQUIPED WITH MULTIPLE ANTENNAS IN A HIGH SPEED PACKET DATA SYSTEM}

1 is a diagram schematically illustrating a wireless environment of a CDMA fast packet data system to which the present invention is applied.

2 is a block diagram illustrating a configuration of an apparatus for controlling a dynamic range of weights applied to a combiner of a mobile terminal in a high speed packet data system according to the present invention.

3A is a diagram illustrating a state in which a distribution of combined signals input to a channel decoder for each coupling scheme is different in a mobile terminal of a typical high speed packet data system;

3B is a view showing a state in which the range of the combined signal input to the channel decoder for each combining scheme is the same when the dynamic range of the weight is controlled according to the present invention.

4 is a flowchart illustrating a dynamic range control method of weights applied to a combiner of a mobile terminal according to the present invention.

The present invention relates to a method and apparatus for receiving a terminal in a high speed packet data system of a code division multiple access method. In particular, in a terminal using various combining methods, a dynamic range of weights is controlled for each combining method to match an input range of a channel decoder. Device and method.

In general, a mobile communication system uses a frequency division multiple access (FDMA) system that divides a frequency band determined according to a communication method into a plurality of channels and uses a frequency channel allocated to each subscriber, and one frequency channel. Time Division Multiple Access (TDMA), where multiple subscribers use time-division, and code division multiple access, in which multiple subscribers use the same frequency band in the same time zone and assign different codes for each subscriber Code division multiple access (CDMA) and the like. Such mobile communication systems are currently reaching a stage of providing high-speed data services capable of transmitting a large amount of digital data such as e-mail, still images, and moving images to mobile terminals as well as general voice call services according to the rapid development of communication technology.

Representative examples of mobile communication systems that provide high-speed data services using the CDMA method include problems of EV-DO (Evolution Data Only), which enables high-speed data transmission, and EV-DO, which cannot simultaneously support voice and packet services. Evolution of Data and Voice (EV-DV) has been proposed for this purpose. The EV-DO is one of the high speed data service standards proposed by Qualcomm of the United States for the transmission of a large amount of digital data, and is designed to provide a forward transmission speed of about 2.4 Mbps by evolving the conventional CDMA 2000 1x. will be.

In the CDMA high-speed packet data system, a radio signal transmitted from a base station is reflected to various scatterers near the mobile station to arrive at the mobile terminal. Adjacent base stations when frequency selective fading due to frequency selective fading, time selective fading due to Doppler spread generated by the movement of the mobile terminal, and frequency reusability near 1 Due to co-channel interference received from the high-quality high-speed packet data service is difficult.

As a communication technology to solve this problem, a multiple input multiple output (MIMO) technique, which is one of multiple antenna schemes, has been proposed. When the base station transmits the high speed packet data to the mobile terminal, the diversity gain increases as the number of antennas of the base station related to transmit diversity increases and the number of antennas of the mobile terminal related to receive diversity increases. It is known that the attenuation and interference can be effectively reduced, and the angle spread of the path received by the antenna of the mobile terminal is small, and when the angle of incidence of each path is different, the interference by the multipath can be reduced by using the multiple antenna. As a result, communication systems using multiple antennas have been developed.

However, since the size of the mobile terminal is limited, it is difficult to mount two or more antennas in reality. When a mobile station moves from a base station maintaining a current link to a neighboring base station, connecting a link with another base station while maintaining the current link is called soft handoff. A synchronous CDMA system is a base station. With this unique short pseudo-noise (PN) code, it is possible to maintain the link simultaneously with two or three base stations with a frequency reuse rate of one.

On the other hand, TDMA systems cannot communicate with two base stations simultaneously in the same time slot, and FDMA systems cannot communicate with two base stations simultaneously in the same frequency slot. It is relatively difficult to implement soft handoff while keeping it close. While soft handoff can be easily implemented using the CDMA scheme, there is a disadvantage that signals from neighboring base stations act as interference when a link is maintained with one base station without soft handoff.

In the CDMA scheme, a Walsh code is a code having orthogonality distinguished for each mobile terminal. Orthogonality is satisfied when Walsh codes are aligned at the same time point on the time axis, while Walsh codes arranged at different time points are not orthogonal, which causes a great interference in a multipath environment. Mitigating this is the short PN code. Two short PN codes that are more than one chip apart act as interference among the signals passing through Walsh decover because the autocorrelation coefficient is close to zero in inverse proportion to the code length. This will reduce the energy of the signal to be made. Nevertheless, if the signal from the neighboring base station serving as interference increases, the relative strength of the signal received from the base station maintaining the current link is reduced, so that the base station must transmit a radio wave with appropriate power control.

Power control is essential, and unlike a voice service that simultaneously transmits radio waves to a plurality of mobile terminals, in an EV-DO and EV-DV system, a base station simultaneously transmits data to one mobile terminal. Accordingly, in the EV-DO and EV-DV systems, the forward packet data channel is characterized by a time division scheme and a data rate is determined through rate control rather than power control. For high speed data service, the forward packet data channel uses multiple Walsh codes, and if both Walsh codes are used to support soft handoff, time slots on the time axis for one terminal in two or three base stations Allocating is complicated.

Therefore, the EV-DO and EV-DV systems proposed by the 3GPP2 (Third Generation Partnership Project 2) standardization organization do not use soft handoff in the forward packet data channel. Therefore, the packet data for the other mobile terminal transmitted from the neighboring base station to the packet data received from the base station that the specific mobile terminal maintains the link acts as the same channel interference signal, so a technique for reducing the interference signal is required.

To this end, in the EV-DO and EV-DV systems, a receiving end of a mobile terminal with multiple antennas includes a rake receiver, allocates a finger to each multipath, and descrambles a short PN code signal. descrambling, and channel estimation is performed to multiply and combine the descrambled signal with an appropriate weight. The combined signal is despread through Walsh decover, and the transmission bit is determined through a soft metric generator and an error correcting decoder.

The combined signal obtained by multiplying the descrambled signal by a weight is input to a channel decoder, and there are various methods of combining the calculated weight. Although the range of the combined signal varies according to each combining scheme, the input range of the channel decoder to which the combined signal is input is generally limited. Therefore, there is a need for a technique for controlling the dynamic range of the weights to fit the input range of the channel decoder while using various coupling schemes.

The present invention provides an apparatus and method for preventing performance degradation of a channel decoder of a terminal having multiple antennas and using various coupling schemes in a fast packet data system of a code division multiple access scheme.

In another aspect, the present invention provides an apparatus and method for controlling a dynamic range of weights for each coupling scheme to have a multi-antenna in a code division multiple access high speed packet data system and to fit the input range of a channel decoder of a terminal using various coupling schemes. to provide.

An apparatus of the present invention is a device for controlling a range of weights for generating a combined signal of a mobile terminal using a plurality of combining schemes and having multiple antennas in a high-speed packet data system of a code division multiple access scheme. A channel estimator for receiving a pilot symbol and calculating a channel estimation value of a corresponding reception path for each antenna, an autocorrelation matrix calculator for calculating an autocorrelation matrix value for each predetermined chip period from the received pilot symbol, and a channel of the plurality of combining schemes A weight vector calculator for calculating a corresponding weight vector using the channel estimation value and / or the autocorrelation matrix value according to a coupling method selected according to an environment, and determining whether to modify the weight vector according to the selected coupling method and determining the weight Scale if you need to modify the vector And a combiner for outputting the combined signal by multiplying the descrambled signal by the weight vector output from the controller.

In the method of the present invention, a method for controlling a range of weights for generating a combined signal of a mobile terminal having multiple antennas and using a plurality of combined schemes in a fast packet data system of a code division multiple access scheme, comprising: a pilot transmitted from a base station Receiving a symbol, calculating a channel estimation value of a corresponding reception path for each antenna, and calculating an autocorrelation matrix value for each chip section determined from the received pilot symbols; and according to a coupling method selected according to a channel environment among the plurality of coupling methods. Calculating a corresponding weight vector using the channel estimate value and / or the autocorrelation matrix value, determining whether to correct the weight vector according to the selected combining method, and using a scale factor when the weight vector needs to be corrected. To calculate the corrected weight vector And further characterized in that the descrambled signal comprises the step of outputting the combined signal by multiplying the weight vector outputted from the controller.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

First, a radio environment of a CDMA type high-speed packet data system to which the present invention is applied will be briefly described with reference to FIG. 1 to help understanding of the present invention. In addition, the high-speed packet data system to which the present invention is applied will be described taking an EV-DV and EV-DO system as an example, but it should be noted that the present invention is not limited to the EV-DV and EV-DO system. In addition, in the present embodiment, it is assumed that the multiple antennas of the mobile terminal are two for convenience of description.

The system of FIG. 1 includes a base station 102, 104, a mobile terminal 106 for transmitting and receiving wireless signals to and from the base stations 102 and 104, and a structure 108 for creating a multipath environment in which the wireless signal is transmitted. do. In the example of FIG. 1, the first base station 102 and the second base station 104 each have one transmitting antenna 112, and the mobile terminal 106 has multiple antennas 116, 118. Assuming the mobile terminal 106 maintains a link with the first base station 102 and receives an interference signal from the adjacent base station 104, the mobile terminal 106 is transmitted from the base stations 102 and 104. The signals needed to demodulate the signals are four paths (X _1,1 , X _2,1 , X _1,2 , X _2,2 ), and the interfering signals are signals of two paths (Y _1,1 , Y _1,2 ).

In multipath, the signal by the first path is (X _1,1 , X _2,1 ) and the signal by the second path is (X _1,2 , X _2,2 ). The first subscript of each path signal described above is a number that distinguishes the antennas 116 and 118 of the mobile terminal 106, and the second subscript is a number that distinguishes the path. Based on the same transmission information transmitted from the base station 102, since the signal of the second path is a signal reflected through the structure 108, a long delay is generated compared to the signal of the first path. This transmission delay can be distinguished when it is larger than one chip in the CDMA method.

The multipath channel has more than one transmission path, and the distance between the antennas 116 and 118 of the mobile terminal 106 is usually less than half of the transmission propagation wavelength, and the chip length of the CDMA scheme is longer than the length of the transmission propagation wavelength. Therefore, the delay between X _1,1 and X _2,1 is ignored, and the delay between X _1,2 and X _2,2 can be ignored.

2 is a block diagram illustrating a configuration of an apparatus for controlling a dynamic range of weights applied to a combiner of a mobile terminal in a high speed packet data system according to the present invention.

In FIG. 2, a channel estimator 202 estimates a channel allocated to a corresponding reception path for each antenna through a finger using a pilot symbol known to a base station and a terminal, and the channel is estimated. The estimated values h ₁ (k), ..., h _L (k) are output.

는 첫 번째 안테나의 l 번째 경로에 할당된 핑거의 채널 추정값이며,

는 두 번째 안테나의 l 번째 경로에 할당된 핑거의 채널 추정값을 의미한다.In Equation 1, the variable k is a chip index,

Is the channel estimate of the finger assigned to the l th path of the first antenna,

Denotes a channel estimate of the finger assigned to the l-th path of the second antenna.

과

는 파일럿 심볼로부터 구할 수 있다.In Equation 1, T denotes a transpose matrix, and a channel estimation value.

and

Can be obtained from pilot symbols.

이면, 그 구간에서

은 칩 인덱스 k 에 상관없이 동일한 값을 갖는다.In the EV-DV system, the channel estimate of the channel estimator 202 is updated once every interval (64 chips or 128 chips) between two pilot symbols. If the length of the pilot symbol is 128 chips, the channel estimate is

If in that section

Has the same value regardless of the chip index k.

이라면,

은 k에 따라 다를 수 있다.In the EV-DO system, a channel value of a data portion (800 chip) between two pilot symbols is estimated by smoothing or interpolating from two or more received pilot symbols. Where the channel estimate is

If

May vary depending on k.

Since the structure of the channel estimator 202 in the EV-DV and EV-DO systems is well known to those skilled in the art, a detailed description thereof will be omitted.

In FIG. 2, an autocorrelation matrix calculator 204 estimates noise variance and noise covariance from pilot symbols received from a base station, thereby autocorrelation matrix R ₁ (k), ..., R _L (k)) is output.

For example, in the EV-DV system, the autocorrelation matrix value is updated once every interval (64 chips or 128 chips) between two pilot symbols, and in the EV-DO system, the autocorrelation matrix is once every half slot (1024 chips). The value is updated.

Equation 2 shows the autocorrelation matrix.

는 첫 번째 안테나의 l번째 경로에 할당된 핑거에서 추정된 PN 디스크램블링된 신호의 제1 잡음 변화(noise variance)이고,

는 두 번째 안테나의 l번째 경로에 할당된 핑거에서 추정된 PN 디스크램 블링된 신호의 제2 잡음 변화(noise variance)이며,

는 상기 제1 및 제2 잡음 변화에 대한 covariance이고, *는 conjugate를 의미한다. 상기 자기 상관 행렬 R_l(k)는 다중 경로의 개수만큼 존재한다.In Equation 2

Is the first noise variance of the PN descrambled signal estimated at the finger assigned to the lth path of the first antenna,

Is the second noise variance of the PN descrambled signal estimated at the finger assigned to the lth path of the second antenna,

Denotes a covariance of the first and second noise changes, and * denotes a conjugate. The autocorrelation matrix R _l (k) exists by the number of multipaths.

Since the method of estimating the noise variation and the covariance is well known to those skilled in the art, a detailed description thereof will be omitted.

In FIG. 2, the weight vector calculator 206 uses the channel estimation value of Equation 1, the autocorrelation matrix value of Equation 2, and a combination method selected from the following three combination methods. The weight corresponding to the combining method is calculated. Therefore, the weight vector calculator 206 includes an algorithm for performing the set combining scheme.

The receiver of the mobile terminal generates a combined signal by multiplying the descrambled received signal by the weight, and there are various schemes for the combining scheme as is well known. Representative coupling methods include pilot weighted combining (PWC), maximum ratio combining (MRC), and minimum mean-square error combing (MMSEC).

The PWC method is a method of determining an output signal of a channel compensator (not shown) as a weight, and the MRC method is a method of determining a weight in consideration of a change in noise of an output signal of each descrambled finger. In the MMSEC method, since the output signals of two fingers having the same reception path from two antennas are correlated with each other, weights are determined in consideration of the correlation value. The dynamic range of each of the combined signals outputted through the above three coupling schemes depends on what the coupling scheme is.

Hereinafter, the weight vector calculation formulas for the PWC, MRC, and MMSEC schemes and the advantages and disadvantages of the corresponding coupling scheme will be briefly described with reference to Equations 3 to 5 below. The above three binding methods exemplify typical binding methods, and other binding methods may be applied to the present invention.

First, in the PWC method, the weight vector is calculated as in Equation 3 below.

The PWC scheme has a merit of being easy to implement although its performance is lower than that of other coupling schemes.

In addition, in the MRC method, the weight vector is calculated as in Equation 4 below.

The MRC scheme provides universal performance and is easier to implement than the following MMSEC scheme.

In the MMSEC method, the weight vector is calculated as in Equation 5 below.

The MMSEC method guarantees higher performance than the PWC method and the MRC method, but has a disadvantage in that it is difficult to implement.

3A is a diagram illustrating a state in which a distribution of combined signals input to a channel decoder for each coupling scheme is different in a mobile terminal of a general high speed packet data system.

3a shows weights w ₁ (k) calculated through Equations 3 to 5 in the output signals y ₁ (k), ..., y _L (k) of the descrambled finger. When multiplying .., w _L (k), the distribution of the probability density function (PDF) of the combined signal output from the combiner 210 is shown for each combination method.

Therefore, if the weights w ₁ (k), ..., w _L (k) output from the weight vector calculator 206 of FIG. 2 are used as they are, the combined signal output from the combiner 210 is input to the channel decoder. It can be seen that the range is different for each coupling method.

In general, the input range of the soft metric generator included in the channel decoder has a limited range in consideration of the complexity of the channel decoder, and a combining method used basically when determining the input range is, for example, a PWC method. However, when the MRC method or the MMSEC method use the weights calculated from other combination methods as they are, the input bit range of the combined signal is different, so the performance of the channel decoder having the limited input range is degraded.

Therefore, in order to minimize performance deterioration of the channel decoder even if various coupling methods are used, it is necessary to adjust the range of the combined signal inputted to the channel decoder-outputted from the combiner 210. To this end, the present invention controls the dynamic range of the weights output from the weight vector calculator 206.

That is, in FIG. 2, the weight vector calculator 206 calculates the weights w ₁ (k), ..., w _L (k) according to a channel environment by using a method selected from the PWC method, the MRC method, or the MMSEC method. The calculated weight is input to the controller 208. Further, the controller 208 is any coupling method is selected, even to fit to an input range of the channel decoder <Equation 6> to <Equation 8> Edit to control the dynamic range of the use weight weight (v ₁ ( k), ..., v _L (k)) 3B is a diagram illustrating a state in which a range of a combined signal input to a channel decoder for each combining scheme is the same when the dynamic range of weights is controlled according to the present invention.

That is, the controller 208 of FIG. 2 controls a dynamic range of weights that generate input signals of the Walsh despreader and the soft value generator (not shown), that is, a combined signal input to the channel decoder.

First, in the present invention, the scale factor Z (k) for controlling the dynamic range of the weight is defined as in Equation 6 below.

In Equation 6, L denotes the number of multipaths, h _l (k), and superscript H in w _l (k) denotes a Hermitian transpose matrix. For example, if the vector x is x = [1+ j, 2-3 * j] ^T , then x ^H = [1-j, 2 + 3 * j]. Where T is a transpose matrix, x is a column vector, and x ^H is a row vector. By H, Z (k) has real value with imaginary value of zero.

The modified weight V ₁ (k) output from the controller 208 is used by delaying the scale factor of Equation 6 as shown in Equation 7 below.

In Equation 7, the variable P has a positive value, and the delay function f of the scale factor may be defined as shown in Equation 8 below.

The scale factor is for adjusting the combined signal combined by the weight vector to suit the decoder's input data range, and the variable P using the scale factor delayed by several chip intervals. This is to determine whether to obtain a modified weight v _l (k).

In Z (k-64) of Equation 8, &quot; 64 &quot; is an example in which an interval between two pilot symbols is 64 chips in an EV-DV system. In other cases, it is set to the value of the corresponding chip section.

라하고, 두 번째 안테나의 l번째 경로에 할당된 핑거의 PN 디스크램블링된 신호를

라 할 때 결합기(210)로 입력되는 디스크램블링된 수신 신호

는 하기 <수학식 9>와 같이 정의된다.The PN descrambled signal of the finger assigned to the lth path of the first antenna is

The PN descrambled signal of the finger assigned to the lth path of the second antenna

Descrambled received signal input to combiner 210 when

Is defined as in Equation 9 below.

When the output signal of the combiner 210 is a (k) and the weight modified according to the present invention is V ₁ (k), the a (k) is defined as in Equation 10 below.

In Equation 10, the superscript H denotes a Hermitian transpose matrix, and the Hermit transpose matrix is used to cancel phase rotation generated in the forward channel.

4 is a flowchart illustrating a method for controlling a dynamic range of weights applied to a combiner of a mobile terminal according to the present invention.

In step 401 of FIG. 4, the channel estimator 202 of the mobile terminal that receives the radio signal transmitted from the base station selects a channel allocated to the reception path for each antenna by using a pilot symbol known to the base station and the terminal. Estimate as> In addition, the autocorrelation matrix calculator 204 estimates a noise change and a noise covariance from the pilot symbol and calculates the equation as shown in Equation 2.

In step 403, the weight vector calculator 206 applies the channel estimate value and / or the autocorrelation matrix value to Equations 3 to 5 according to the coupling scheme selected according to the channel environment. Calculate In step 405, the controller 405 checks whether the PWC method is selected as the combined method, and if the PWC method is selected, the controller 405 proceeds to step 407 and does not perform a separate weight correction operation, and the weight calculated from Equation 3 above. Outputs as is.

In operation 407, the combiner 210 multiplies the PN descrambled signal by the weight according to Equation 3, and adds an appropriate delay to the signal output from each finger in step 415 to output the combined signal. .

On the other hand, in step 405, the controller 208 determines whether the PWC scheme is selected as the combining scheme, and when a coupling scheme other than the PWC scheme is selected, the controller 208 proceeds to step 409 in which the channel estimation value and the corresponding combining scheme are Calculate the scale factor using the weights.

Thereafter, in step 411, the controller 208 multiplies the scale factor delayed by the weight of Equation 3 according to Equation 7 and outputs a weight modified according to the input range of the channel decoder. In operation 413, the combiner 210 receives the modified weight and multiplies the modified weight by the descrambled signal, and adds an appropriate delay to the signal output from each finger in operation 415 to output the combined signal.

As described above, according to the present invention, performance degradation of the channel decoder can be minimized even when various coupling methods are used for data reception at the terminal of the CDMA fast packet data system.

In addition, according to the present invention, it is possible to control a dynamic range of weights multiplied by a PN descrambled signal in a mobile terminal of a high speed packet data system using various combining schemes.

In addition, according to the present invention, in a mobile terminal of a high speed packet data system using various coupling schemes, various coupling schemes may be used depending on the channel environment without changing the precision of the data path behind the combiner.

Claims (10)

An apparatus for controlling a range of weights for generating a combined signal of a mobile terminal having a plurality of antennas and using a plurality of combining schemes in a code division multiple access high speed packet data system, A channel estimator for receiving a pilot symbol transmitted from a base station and calculating a channel estimation value of a corresponding reception path for each antenna; An autocorrelation matrix calculator for calculating an autocorrelation matrix value for each predetermined chip interval from the received pilot symbols; A weight vector calculator for calculating a corresponding weight vector using the channel estimate value and / or the autocorrelation matrix value according to a combination method selected according to a channel environment among the plurality of combination methods; A controller for determining whether to modify the weight vector according to the selected combining scheme and outputting the modified weight vector using a scale factor when the weight vector is to be corrected; And a combiner for outputting a combined signal by multiplying the descrambled signal by the weight vector output from the controller. The method of claim 1, The plurality of combination methods may include at least two of a pilot weighted combining (PWC) method, a maximum ratio combining (MRC) method, and a minimum mean-square error combing (MMSEC) method. Dynamic region control device of the weight, characterized in that it comprises a. The method of claim 1, The scale factor calculated in the controller Z (k) is defined as in Equation 11 below,

W (k) is a weight vector according to the selected combining scheme, h (k) is a channel estimate value, and L is the number of multipaths, superscript H at h _l (k), w _l (k) Is a weighted dynamic range control device, characterized in that the Hermitian transpose matrix. The method of claim 3, wherein The modified weight V _l (k) output from the controller is used by delaying the scale factor as shown in Equation 12 below.

Wherein P is a positive value and means a chip interval for weights modified using a delayed scale factor, and f is a delay function of the scale factor. The method of claim 4, wherein When the mobile terminal has two antennas The descrambled signal of the lth path of the first antenna

The descrambled signal of the lth path of the second antenna

Descrambled signal input to the combiner when

Is defined as in Equation 13 below,

The combined signal is defined as in Equation (14) when the combined signal is a (k) and the modified weight is V ₁ (k). A method for controlling a range of weights for generating a combined signal of a mobile terminal having a plurality of antennas and using a plurality of combining schemes in a code division multiple access high speed packet data system, Receiving a pilot symbol transmitted from a base station, calculating a channel estimation value of a corresponding reception path for each antenna, and calculating an autocorrelation matrix value for each chip period determined from the received pilot symbol; Calculating a corresponding weight vector using the channel estimation value and / or the autocorrelation matrix value according to a coupling method selected according to a channel environment among the plurality of coupling methods; Determining whether to correct the weight vector according to the selected combining method and calculating a modified weight vector using a scale factor when the weight vector is to be corrected; And multiplying the descrambled signal by the weight vector outputted from the controller to output a combined signal. The method of claim 6, The plurality of combination methods may include at least two of a pilot weighted combining (PWC) method, a maximum ratio combining (MRC) method, and a minimum mean-square error combing (MMSEC) method. Dynamic range control method of the weight, characterized in that it comprises a. The method of claim 6, The scale factor calculated by the controller Z (k) is defined as in Equation 15,

W (k) is a weight vector according to the selected combining scheme, h (k) is a channel estimate value, and L is the number of multipaths, superscript H at h _l (k), w _l (k) Is a Hermitian transpose matrix. The method of claim 8, The modified weight V _l (k) output from the controller is used by delaying the scale factor as shown in Equation 16 below.

P denotes a chip interval for weights having a positive value and modified using a delayed scale factor, and f is a delay function of the scale factor. The method of claim 9, When the mobile terminal has two antennas The descrambled signal of the lth path of the first antenna

The descrambled signal of the lth path of the second antenna

Descrambled signal input to the combiner when

Is defined as in Equation 17 below.

And assuming that the combined signal is a (k) and the modified weight is V ₁ (k), the combined signal is defined as in Equation (18).

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